Group, Wasn't their someone on here or maybe mentioned on here who specializes in tube tester repair and calibration? A friend has a TV-7D that fails everything he tests in it. Robert Downs - Houston <http://www.wa5cab.com> (Web Store) MVPA 9480 <wa5cab at cs.com> (Primary email) <wa5cab at houston.rr.com> (Backup email)